Presentation on theme: "Electromagnetic Radiation"— Presentation transcript:
1 Electromagnetic Radiation LightElectromagnetic RadiationEM RadiationEM SpectrumTypes of EM Radiation
2 A. EM Radiation E=mc2 Electromagnetic Radiation transverse waves produced by the motion of electrically charged particlesdoes not require a mediumspeed in a vacuum = 300,000 km/selectric and magnetic components are perpendicularE=mc2
3 A. EM Radiation Photons tiny, particle-like bundles of radiation absorbed and released by electronsenergy increases with wave frequency
4 B. EM Spectrumlong low flow energyshort high fhigh energy
5 C. Types of EM RadiationRadiowaveslowest energy EM radiation
6 C. Types of EM Radiation Radiowaves FM - frequency modulation AM - amplitude modulationMicrowavespenetrate food and vibrate water & fat molecules to produce thermal energy
7 C. Types of EM Radiation Infrared Radiation (IR) slightly lower energy than visible lightcan raise the thermal energy of objectsthermogram - image made by detecting IR radiation
8 C. Types of EM Radiation Visible Light small part of the spectrum we can seeROY G. BIV - colors in order of increasing energyROYG.BIVredorangeyellowgreenblueindigoviolet
9 C. Types of EM Radiation Ultraviolet Radiation (UV) slightly higher energy than visible lightTypes:UVA - tanning, wrinklesUVB - sunburn, cancerUVC - most harmful, sterilization
10 C. Types of EM Radiation Ultraviolet Radiation (UV) Ozone layer depletion = UV exposure!
11 C. Types of EM Radiation X rays higher energy than UV can penetrate soft tissue, but not bonesUsed to be used to size shoes before harmful affects were known.
12 Radiation treatment using radioactive cobalt-60. C. Types of EM RadiationGamma rayshighest energy EM radiationemitted by radioactive atomsused to kill cancerous cellsRadiation treatment using radioactive cobalt-60.
13 CHECK UNDERSTANDING1. A light wave is an electromagnetic wave that has both an electric and magnetic component associated with it. Electromagnetic waves are often distinguished from mechanical waves. The distinction is based on the fact that electromagnetic waves ______.a. can travel through materials and mechanical waves cannotb. come in a range of frequencies and mechanical waves exist with only certain frequenciesc. can travel through a region void of matter and mechanical waves cannotd. electromagnetic waves cannot transport energy and mechanical waves can transport energye. electromagnetic waves have an infinite speed and mechanical waves have a finite speed
14 All waves have the same speed which depends on the medium Check Understandinga. Which region of the electromagnetic spectrum has the highest frequency?b. Which region of the electromagnetic spectrum has the longest wavelength?c. Which region of the electromagnetic spectrum will travel with the fastest speed?GAMMA RAYRADIO WAVEAll waves have the same speed which depends on the medium
15 Check Understandinga. Which color of the visible light spectrum has the greatest frequency?b. Which color of the visible light spectrum has the greatest wavelength?VIOLETRED
16 LightII. Light and ColorLight and MatterSeeing ColorsMixing Colors
17 A. Light and Matter Opaque absorbs or reflects all light Transparent allows light to pass through completelyTranslucentallows some light to pass through
18 B. Seeing Colors White light contains all visible colors - ROY G. BIV In white light, an object…reflects the color you seeabsorbs all other colorsREFLECTSALL COLORSABSORBSALL COLORS
19 Video: How Cones and Rods Work Stimulates red & green cones B. Seeing ColorsVideo: How Cones and Rods WorkStimulates red & green conesThe retina contains…Rods - dim light, black & whiteCones - colorred - absorb red & yellowgreen - absorb yellow & greenblue - absorb blue & violetStimulates all cones
20 Test for red-green color blindness. B. Seeing ColorsTest for red-green color blindness.Color Blindnessone or more sets of cones does not function properly
21 View Java Applet on primary light colors. C. Mixing ColorsPrimary light colorsred, green, blueadditive colorscombine to form white lightEX: computer RGBsView Java Applet on primary light colors.
22 View Java Applet on filters. C. Mixing ColorsFiltertransparent material that absorbs all light colors except the filter colorView Java Applet on filters.
23 C. Mixing Colors Pigment colored material that absorbs and reflects different colorsPrimary pigment colorscyan, magenta, yellowsubtractive colorscombine to form blackEX: color ink cartridges
24 C. Mixing Colors Light Pigment When mixing pigments, the color of the mixture is the color of light that both pigments reflect.